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What is the problem and what is known about it so far?

Obstructive sleep apnea (OSA) is a problem in which a person's oxygen levels decrease repeatedly while the person is sleeping due to repeated obstructions occurring at the back of their throat. Although many people with OSA snore, some do not. Without treatment, OSA can lead to daytime fatigue as well as an increased risk for other medical problems, including cardiovascular disease. Treatment frequently involves wearing a specialized mask during sleep. Diagnosing OSA has traditionally required that the patient sleep at a laboratory where special monitors can be applied. More recently, many studies have been performed in patients' homes because it is more convenient. However, many studies done at home have a reduced number of recording channels and do not provide as much information to the physician as laboratory studies.

Why did the researchers do this particular study?

To find out whether at-home studies with fewer recording channels can enable physicians to make the same diagnosis and treatment recommendations as full laboratory studies, and to find out whether the approaches differ in how well patients feel after treatment.

Who was studied?

406 patients who were referred by their physicians to a sleep clinic because of concern about possible OSA.

How was the study done?

All of the patients had a sleep study performed in a laboratory, and patients were randomly assigned to 3 groups. In the first group, the patients' physicians received all of the information from the laboratory study. In the second group, the physicians received information from a reduced number of recording channels that replicates the type of monitoring typically conducted when studies are done in the patients' homes (a “level 3 study”). In the third group, the physicians received even less information to mimic an even simpler type of at-home study (a “level 4 study”). The researchers collected information on what diagnoses the physicians made and how confident they were in them. They also tested how well the patients felt with treatment after 4 months.

What did the researchers find?

Overall, the types of diagnoses and treatments recommended were similar among the 3 groups. Physicians felt less confident, however, in the diagnoses they made in the level 4 group (which had the least amount of information provided). Patients' symptoms improved in all 3 groups, and there was no difference between the group whose physicians received all of the information from the laboratory study and those in the group with more limited information (level 3). However, the study was not able to determine whether symptoms improved as much for patients whose physicians received the least amount of information from the sleep study (level 4).

What were the limitations of the study?

All of the information provided to the physicians came from a study that was done in a laboratory, and it is not known whether the results would have been similar if the information had been collected in the patients' homes, as would be done with the more limited types of studies used in real-world practice.

What are the implications of the study?

It seems that certain types of sleep studies performed in patients' homes may be safely used to evaluate and treat certain people who are believed to have OSA. These findings need to be confirmed with studies that are actually performed in patients' homes.

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